Phrasal verb.

[Rezia]

Should a phrasal verb be regarded as a word or a word combination?

[Dark]

My intuition prompts me that it must be regarded as a word, i.e. a single syntactical unit. Compare it with idioms. In accordance with generative syntactic theory, idioms cannot be split apart and leave their chunks behind.
For example, in the sentence "He kicked the bucket" meaning "He died", the word combination "kick the bucket" is equal to the word "die" and, consequently, must occupy the same slot in the syntactic structure of the sentence. Similarly, "give up" and "surrender" look absolutely alike according to the Uniformity of Theta-Assignment Hypothesis.

[Rezia]

Yes, I see. Well, from this point of view  idioms also should be regarded as a word then?

[Dark]

Well, actually, it's an arguable issue. On the one hand, the elements of an idiom are parts of certain syntactic structure. But on the other hand, if we can replace a string of lexical units with a single lexical unit and fully preserve the meaning... Notice that the first mechanism that is involved in the process of speech generation is the lexicon. It picks the lexical units - "the blocks" - which will be used by syntax for building up the structure afterwards. And only after that the phonology will join the game and spell it out in an appropriate way.
Thinking logically, if the word "to die" and its euphemism "to kick the bucket" mean exactly the same and their distribution depends on the stylistic effect only, then they should take the same position in a syntactic structure. After all, if you say about someone that he "kicked the bucket", you know that there is actually no bucket and he didn't really kick anything... That is why I regard this string of words as a single element.
Correct me if I am mistaken.

[Rezia]

You are not mistaken. The matter is that different points of view do exist. Considering an idiom as a word we get a problem with proverbs then. They are sentences, a predicative unity. They can't be regarded as a word and they are idioms. You'll find proverbs in any dictionary of idioms.

[Dark]

Ah... It's a different kettle of tea!    Proverbs are full sentences with complete syntactic structures, they convey some message which may be perceived only when the hearer receives them as whole entities. At the same time, things like "kick the bucket" or "do away with" only substitute a verb.

[Rezia]

No, it's not a different pair of shoes.    A proverb is an idiom as well as some verbal expression. And some verbal idioms can split from syntactic oint of view. E.g. He drinks like a fish. "drinks" will be a predicate and ''like a fish' adverbial modifier.

[Dark]

I agree... Then there must be some subdivision among different idioms... Look! In the example, that you have given, "like a fish" can replace another phrase of that kind or some adverb ... like "much", for example... But in both cases they are adjuncts and do not form a single constituent with the verb... They both are optional. You can say "He drinks" simply omitting the adjunct... But you can't say "He kicked" in the meaning of "He died"...
I would put it the following way: "An idiom cannot be split if it forms a single constituent like a VP, an AP or a DP including all their arguments". That sounds reasonable, I think...

[Rezia]

"An idiom cannot be split if it forms a single constituent like a VP, an AP or a DP including all their arguments".

Oh, of course, it can! "He kicked the damn bucket!" 

[Dark]

I don't like it.

[Rezia]

Why?